Engine starter gearing



April 30, 1940- SEKELLA 2.199.349

ENGINE STARTER GEARING F iledvJuly s, 1938 s Sheets-Sheet 1 April 30, 1940.

Y. \SEKELLA 9.349

ENGINE STARTER GEARING Filed July 8, 1938 3 Sheets-Sheet 2 Lddnes/s: v BY gousim fiekeda,

' ATTORNEY.

April 30, 1940.

- Y. SEKELLA ENGINE STARTER GEARING Filed July 8, 193a 3 Sheets-Sheet s BYJJMJ Patented A 30, 1940 OFFICE- Youston Sekella, Elmil-a Heights, N. Y., aslignor to Bendix Aviation Corporation, South Bend.- Ind., a corporation of Delaware Application.July s, 1a3s, Serial No. 21s,15c

11 Claims. The present invention relates to engine'starter gearing and more particularlyto *a yielding driving connection of the automatically engaging and disengaging type for connecting'a' starting motor with a member of the engine to be-started.

It is an object of the present invention to provide a novel engine starter drive which is eflicient and reliable in operation while being simple and economical in construction.

It is another object to provide such a device which is completely self-contained and enclosed against the entry of foreign matter.

It is a further object to provide such a device incorporating a yielding driving connection comprising a member of elastically deformable material which is arranged to yield both torsionally and compressively.

It is another object to provide such a device in which the elastic memberis in the form of a cylindrical block of rubber or the like, with special provisions for preventing jamming or sticking. H

It is another object to provide such a device in which the meshing position of the pinion is accurately defined irrespective of load conditions.

It is another object to provide such a device in which the torque is transmitted frictionally through the elastic member acting 'asja member of a friction'clutch which isautomatically tight f ened as the torque is applied thereto.

Itis a further object to provide such a device incorporating a self-contained anti-drift n echanism for normally retaining the gearing in disengaged position. f I v It is another object to provide such a device incorporating a self-contained rebound check for preventing the gearing from'boundi'ng back and striking the engine member after being thrown out of engagement therewith.

It is another object toprovide such a device incorporating provisions whereby the disengagement of the drive connection may be delayedo prevented-as long as the starting motor remains energized. i

Further objects and advantages will be apparent from the following description taken in connection with the accompanying drawings in Fig. '1 is a side elevation partly in section ofa second third embodiment of the invention, showing the' parts in driving position; Fig. 7 is an end view thereof;

Fig. 8 is a side elevation partly in section of a fourth embodiment of the invention;

Fig. 9 is an end view thereof; and

Fig. 10 is a detail view in perspective of various 7 elements of the drive' structure illustrated in Fig. 8, certain of the parts thereof being broken for automatically traversing the pinion into engagement with the engine gear responsive to acceleration of the power shaft l are provided comprising a'hollow shaft 4 threaded adjacent one end as indicated at 5 and having its opposite end smooth and anchored to the power shaft by suitable means such as a pin 6 traversing said shafts.

A driving member in the form of a nut i is mounted on the threaded end 5 of the hollow screw shaft [so as to be'automatically traversed along the shaft by relativerotation therebetween.

Means for transmitting longitudinal movement oi the nut I to the pinion 2' in .a direction to mesh the pinion is provided in the form of flange members 8 and 9 suitably afiixed to the nut and pinion respectively, and a yielding transmission member in the form of a cylindrical block H r j elastically deformable material such as rubber" loosely. mounted on the nut I and engagingatitsf ends the fian ges'8 and 9., The ends of block II are preferablytapered or beveled as illustrated in order to eliminate any tendency for the block to stick or jam when compressed and subjected to torque.

Means for limiting the engaging ovem t of ff the pinion is'provided in the form of, a stop inelnber l2 anchored to'the power shaft I by mea s.

of the pin 6, a barrel member l3 having an in! turned flange I4 acting as a stop "for the flange. ,9'

of the pinion, and a thrust ring s r'etain ediin 1 the opposite end of the barrel l3 ,by suitable means such as a split ring 16. A friction thrust washer I! may be interposed between thefstop member l2 and thrust ring l5 to'form' a frictional connection therebetween when the partsfare'in operative position as illustrated'in Figfit. The

thrust ring i5 is preferably splinedjinthe 'end of the barrel l3 asby means of lugsio'extending radially from said thrust ring into-'islot's' will the end of the barrel; I he a nchor pin "6 is retained by suitable means such'as a splitring l0 seated in a circumferential groovein' said stop member andpin.

Means normally maintaining the position asillustrated in Fig. 1 is provided in the in the barrel I3 bearing at one end against the thrust washer I1 and at the other end against a thimble I9 seated on the stop member I2. A reentry spring 2I is provided preferably seated in a recess 22 in the stop member I2 and causing a thimble 23 slidably mounted in said recess to engage the end of the nut I and. urge it into initial engagement with the threads 5 of shaft 4. The thimble 23 is retained in the recess 22 by suitable means such as a split ring. 24 which limits the expansion of the re-entry spring 2i.

The normal position of the flange 8 flxed to the nut I within the barrel I I is defined by means 'of a cylindrical thrust sleeve 25 interposed between the flange 8 and the thrust ring I5. The

length of the rubber block is such that it is com-- to initiate meshingaction. When the block -I I is compressed between the flanges 8 and 9, it

transmits torque directly therebetween and-also supplements the transmission of torque to the barrel through the friction thrust washer II by reason of the frictional engagement of the block within the barrel.

Means for frictionally transmitting torque from the barrel I3 to the nut is preferably provided in the form ofa friction ring 28 interposed between the flange 9 on the pinion'2 and the flange I4 of the barrel.

In the operation of this embodiment of the invention, starting with the parts in the positions illustrated in Fig. 1, acceleration of the power shaft I by the starting motor causes the nut I to be traversed to the right along the threads 5. of shaft 4, which motion is transmitted to the pinion 2 and barrel I3 through the rubber block II. The meshing movement of the pinionand barrel assembly is limited by the engagement of the friction washer II on the thrust ring I5 with the stop member I2. Further movement of the 1 nut I compresses'the rubber block II between the flanges 8 and 9, thereby building up pressure for the transmission of torque directly through the block from the nut flange 8 to pinion flange 9. Torque is also transmitted from the stop member I2 to the thrust ring I5 and from the barrel flange I4 to the pinion flange 5 through the friction washers I1 and 25 respectively. The compression of the block II also causes it to frictionally engage the interior of the barrel I I, and the torque so transmitted to the barrel is applied to the pinion through the friction washer 28. The resilient transmission of torque through the block between the nut flange I and pinion flange 9 is controlled and damped by the fric-' tional connections referred to which act in the nature of shock absorbers to damp relative torsional oscillations of the nut and pinion.

When the engine starts, the acceleration of the engine member 3 causes the pinion 2 to overrun the power shaft I whereby the nut member I moves back and relaxes the pressure on the rubber block II. The nut 1 can then overrun freely,

, subject only to the light frictional drag caused mainly by the compression of the anti-drift spring I8. The frictional drag between the pinion and barrel assembly may be arranged to be In some installations, however,

small and the pinion will stay in mesh with the flywheel gear as long as the starting motor remains energized. In such installations, f the engine should fail to continue self-operative after an initial start, the starting motor will pick up the flywheel and continue to rotate it'until a true start is secured.

When the starting motor is deenergized, the

deceleration'of the power shaft I causes traversal parts toward meshing position when so thrown out of mesh. is prevented by the nut I running off the end of the threads 5 and rotating freely on the smooth portion of the shaft 4 until the Initial a momentum of the parts is dissipated. entry ofthe'n'ut 1 into the threads 5is thereafter brought about by the re-entry spring 2I which =thus insures traversal" of the parts upon reactu- 'ation of the power shaft I. I

The embodiment of the invention illustrated in Figs. 4 and 5 is substantially similar to that illustrated in Figs. 1 to 3, and the corresponding parts are similarly numbered. In this case, however, the pinion flange 9' is spllned in the end of the barrel I3 to form a positive driving connection therebetween. As here shown, this splined connectionis obtained by means of radial lugs 4I extending into slots 42 in the barrel, the flange being retained in the barrel by means of a split ring 43.

In order to prevent dust caused by wear of the rubber block II from entering the threads 5 of shaft 4,.which might in course of time impede the traversal of the nut I, a sleeve 44 is here provided loosely mounted in the free end of the rubber block in telescopic relation with v the nut I and cooperating with a thrust ring .to enclose said block.

An optional form of anchorage for the stop member I2 is also here illustrated comprising I .a shoulder 45 on the hollow shaft 4, and a set screw 41 is threaded through the stop member and hollow shaft, having a pilot 48 entering the power shaft I and locked by a retaining ring 49.

The operation of this embodiment of the invention is in general the same as previously described except that the positive connection between the barrel I3 and pinion flange 9' prevents overrunning of the pinion in the barrel when the engine starts. If theblock II is assembled in the barrel with initial friction, demeshing of the pinion is then caused to take place immediately upon overrunning of the power shaft by the pinion in the conventional manner.

In the embodiment of the invention illustrated in Figs. 6 and 7, a power shaft 5I has freely Journalled thereon a pinion. 52 for movement into and out of engagement with a flywheel gear 53 of an engine to be started. A hollow screw shaft 54 is fixed to the power shaft 5I by means of a pin 55 retained by a split ring 56; A nut 51 is threaded on the screw shaft 54 and is yieldably connectedto the pinion 52 by means of a cylindrical block 55 of rubber-like material mounted on the nut 51 and engaging a flange member suitably anchored to the pinion 52 and keyed as indicated at 6| in a barrel mem- L p 7 a oaa ief A thrust sleeve 88 is interposed in the barrel 8 between the thrust ring 85 and the nut 51, and an anti-drift spring 89 is provided engaging the thrust ring 88 and a thimble II mounted on-the stop member to normally maintain the parts in idle position. p

In this embodiment of the invention, the rubber block 58 is formed with tapering end surfaces conforming to tapered portions 12 and 1 8 of the nut 5'! and flange 59 respectively. The block 58 is also formed with a portion l4 fitting 18 with initial friction in the barrel 82 and a portion having initial clearance within the-.bar-

rel 82. In this manner, initial actuation of the pinion 52 from the nut 51 is comparatively light- 7 member 86 through the thrust ring 85 to the 1 barrel and thence to the pinion through the keyed connection of the flange in the barrel. A friction washer may be interposed between the abutment member 86 and thrust ring 85, or the thimble ll may be formed of suitable material to perform the functions of such washer, as illustrated. p

When the engine starts, acceleration of the pinion with its associated parts causes the traversal thereof to idle position. When the nut 51 strikes the ends of the threads on the screw shaft 54, the backward rotation of the nut on the screw shaft is arrested. Inasmuch,

to the nut only through the friction of the block 58, the pinion and barrel continue to overrun until their momentum is dissipated, thus maintaining the nut 51- in its idle position with the venting rebounding of the parts toward the flywheel gear.

In the embodiment 'of the invention illustrated in Figs. 8 to 10, a power shaft 8| has a hollow shaft 82 anchored thereon as by means of a pin 83 retained by a lock ring 84, and a key 85. Shaft 82 is threaded for a portion of its length adjacent one end as indicated at 86, and

a nut member 81 is mounted thereon in position to cooperate with said threads but normally maintained on the smooth portion 88 of shaft 82 beyond the end of said threads.

A pinion 89 is freely journalled on power shaft 65" engagement with a flywheel gear 9| of an engine to beystarted. Meansfor actuating the pinion 8| from nut" 81 are provided comprising a. block 92 of rubber-like material cooperating at oneend with a flange member 93 fixed in any suitwith a coupling member 94 journalled on a reduced portion 95 of shaft 82. member is formed to provide a seat 98 for the free end of the elastic block 92 and is provided however, as the pinion and barrel are connected assistance of the anti-drift spring 89, and pre:

8| for longitudinal movement into and out of V able way to the nut 81 ,andat the other end The coupling with a peripheral flange 91 (Fig.10). having raid ial slots 98. A sleeve member I8I anchored as indicated at I82 to the pinion 89 is provided with radial lugs 99 adapted to enter the slots 98 and connect the coupling member and sleeve for rotation in unison.

Means for enclosing and uniting the parts is provided in the form' of a barrel member I83 having an inturned flange' I84 at one end cooperating frictionally with the flange 93 and provided at its other end with a split ring I88 retaining the end-of the sleeve member I8I therein. Means for preventing disengagement of the lugs 99 of the sleeve member from the slots 98 of the coupling member is provided in the form of a thrust sleeve I88 in the barrel surrounding the block 92 and bearing at its endsagainst the-flange I84 and the coupling member 94 respectively.

v The meshing position of-the pinion 89 is defined by a stop nut I8'I threaded on the reduced nd'of the shaft 82 in position to beengaged by the coupling member 94 when the parts are in operative position.

The parts are normally maintained in idle position as illustrated in Fig. 8 by means of an anti-drift spring I88'interposed between'the stop nut I81 and coupling member 94. Means for urging the nut 81 into initial engagement with to the pinion 89 to cause it to mesh with the engine flywheel gear 9|. When the coupling member 94 engages the stop nut I81, further motion of the nut 81 causes the rubber block 92 to be compressed between the flange 93 and coupling member, thereby building up an elastic frictional connection for transmission of torque to the pinion. Torque is also transmitted directly from the stop nut I8lto the coupling member, for which purpose afriction washer H2 is preferably interposed therebetween.

When the engine starts, overrunning of the pinion is transmitted back through the rubber block to the nut 81, causing it to traverse back to idle position, drawing the pinion. out of mesh, after which the parts overrun freely until their momentum is dissipated. The re-entry spring I89 thereuponcauses the nut-81 to enter the threads 88, in which position the parts are maintained by the anti-drift spring I88.

Although certain forms of the invention have been shown and described in detail, it will be understood that'other forms are possible .and various changes may be made in the design and arrangement of the parts without departing from'the spirit of the invention as defined in they claims appended hereto.

What is claimed is:

1. In an engine starter drive, a shaft, a stop member fixed on one end thereof, a driving member mountedon the opposite end thereof a driven pinion member mounted for longitudinal movement into. and out of engagement with a member 'gear of an engine to be started, means ineluding an elastically deformable transmission driven members, transmitting longitudinal move ment of the driving member to the driven mem-- her to limit the longitudinal movement of the ingmember threaded-on the opposite end theredriven member.

2. In an engine starter drive, a screw shaft, a stop member fixed on one end thereof, a drivof, a driven .member mounted for longitudinal movement into and out of engagement with a member of an engineto be started, means in cluding a yielding transmission member frictionally connecting said driving and driven,menrbers and yieldingly transmitting longitudinal movement of the driving member to the driven memj ion.

ber, and means including a barrel member outside the line of transmission of torque from the driving member to the driven member enclosing the transmission member and cooperating with the stop member to limit theengaging movement I the power shaft for movement into and out of engagement with a member of an engine to be started, means including a block of elastic material frictionally connecting .the clutch member andpinion for rotation and longitudinal movement in unison, and means including a barrel enclosing the drive and engaging the stop member and pinion to limit the travel of the pinion.

4. In' an engine starter drive, a power shaft, a hollow shaft fixed thereon, an abutment fixed on the hollow shaft, a pinion slidably mounted on the power shaft for movement into and out of engagement with a member of an engine to be started, means inchiding a barrel cooperating with the abutment and the pinion to limit the travel of the pinion, and means including a member having an inclined connection with the hollow shaft and a block of elastic material actuated thereby, for resiliently driving the pinion from the hollow shaft, said block forming the sole connection between said member and pinion.

5. In an engine starter drive, a power shaft, a screw shaft fixed thereon, an abutment fixed on the screw shaft, a pinion slidably mounted on the power shaft for movement into and out of engagement with a member of an engine to be started, means including a barrel enclosing the screw shaft cooperating with the abutment and the pinion to limit the travel of the pinion, and means including a nut threaded on the screw shaft and a cylinder of rubber-like material actuated thereby for transmitting longitudinal movement and rotation-to. the pinion and forming the sole connection between the nut and pin- 6. In an engine starterdrive, a power shaft, a screw shaft fixed thereon, a pinion slidably mounted on the power. shaft for movement into and out of engagement. with a mernber of an engine to be started, a nut threaded on-the screw I) shaft; means including a cylinder of rubber-like material surrounding the nut and resiliently traversing and rotating the pinion therefrom, and means including a barrel member surrounding the cylinder, forming an auxiliary frictional driving connection between the power shaft and pinion established after engagement of the pinion with the engine member. X

7. In an engine starter drive, a power shaft, apinion slidably mounted thereon for movement into and out of engagement with a member of an engine to be started, means including a cylinder of rubber-like material surrounding the power shaft and resiliently traversing and rotating the pinion thereon and therewith, and means including a barrel member surrounding thecylinder,

limiting -the traversal ofthe pinion, and providing an auxiliary driving connection between the power shaft and pinion.

8. Inan engine starter drive, a power shaft, a pinion slidably mounted thereon for movement into and out of engagement with -a member of an engine to be started, means including a cylinder of rubber-like material surrounding the power shaft and resiliently traversing and rotating the pinion thereon and therewith, and means including a barrel member enclosing the pinion actuating means and an abutment member fixed to the power shaft, to limit'the engaging movement of the pinion and to provide an auxiliary connection'for transmitting rotation from the power shaft to the pinion.

9. In an engine starter drive, a power'shaft, a pinion slidably mounted thereon for movement into and out of engagement with a member of an engine to be started, means including a block of rubber-like material actuated by acceleration of the power shaft to slide the pinion into angagement with the engine member, and means includingv a barrel member rotated by the power shaft limiting the engaging movement of the pinion and comprising a frictional clutch connection for rotating the pinion from the barrel member.

10. In an engine starter drive, a power shaft,

a pinion slidably mounted thereon for movement intoand out of engagement with a member of v an enginrt to be started, means including a block of rubber-like material actuated by acceleration of the power shaft to slide the pinion into engagement with the engine member, an abutment member fixed to the power shaft, and means enclosing the sliding means limiting the engaging movement of the pinion and frictionally cooperating with the abutment member and pinion to transmit torque from the power shaft to the pinion.

power shaft, means including a barrel member cooperating with the abutment member and pinion to limit thetraversal of the pinion and transbarrel member cooperating with the abutment for normally maintaining the pinion in idle po- I sition.- v

YQUSTON SEKEILA.

- 11. In an engine starter drive, a power shaft,-

- mit rotation thereto, and yielding means in the 

